JP2681600B2 - Construction method of sprayed impermeable sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a spray impermeable sheet, and more specifically, a spray impermeable sheet used for impermeable water at a waste disposal site, a general civil engineering reservoir, a reservoir, a waterway, etc. Regarding the construction method of.

[0002]

2. Description of the Related Art Conventionally, as a water-shielding construction method using a water-blocking sheet for the purpose of blocking water in a waste disposal site, a synthetic rubber or synthetic resin water-blocking sheet is used in a waste disposal site or the like. A sheet water-blocking method is known in which the joints of the water-blocking sheets are laid one on top of the other at the construction site, and then the polymerized portions are bonded with an adhesive.
As disclosed in Japanese Patent Publication No. 6983, after a non-woven fabric is laid on the ground surface, a waterproofing agent comprising a mixture of, for example, a bituminous emulsion and a hydrophilic urethane prepolymer is sprayed on the whole surface of the non-woven fabric. And a method of laying a low-load extensible knitted fabric on the ground surface, as disclosed in Japanese Patent Laid-Open No. 3-147919, or the knitted fabric After laying the ground, in order to fit the knitted fabric to the uneven shape of the ground surface, nails or concrete nails are driven into the recesses and fixed through washers, or a reaction hardening type is used in the recesses instead of the nails. BACKGROUND ART A sprayed water-impervious construction method is known in which, after applying an adhesive, the knitted fabric is laid and fixed by observing the curing time of the adhesive, and then a waterproof agent is applied to form a water-impervious layer.

[0003]

However, among the above-mentioned construction methods, in the case of the sheet impermeable construction method using a synthetic rubber or synthetic resin impermeable sheet, the joint portion between the impermeable sheets is bonded with an adhesive. Or, adhesion is performed by welding, but with the passage of time, this joint part becomes a weak point and water leakage easily occurs, and since the sheet has little flexibility, it is difficult to adapt to unevenness on the ground surface, so that the sheet laying ground The surface needs to be leveled with cement mortar, concrete, etc. to make the uneven surface as flat as possible in advance, and since the sheet is heavy, it takes a lot of labor and time to transport the sheet to the construction site and join the sheets during construction. There are problems such as costs.

In the case of the spraying water-blocking sheet method disclosed in Japanese Patent Publication No. Sho 51-46983 among the above-mentioned construction methods, the elongation of the nonwoven fabric is small. It does not fit and wrinkles when laying,
There is a risk that the sheet will be damaged if a large load is applied during or after construction, and it is necessary to level the uneven surface as much as possible with cement mortar, concrete, etc. before construction as in the above-mentioned sheet impermeable construction method. There are some problems.

Among the above-mentioned construction methods, in the case of the spray water-blocking construction method using the low-load stretchable knitted fabric disclosed in Japanese Patent Laid-Open No. 3-147919, unevenness on the ground surface is more likely to occur than in the case of using a nonwoven fabric. It fits easily, but it does not always fit well.Therefore, the knitted fabric is fixed to the concave portion of the ground surface using nails or concrete nails, or a reaction hardening adhesive. When fixing with concrete nails, one nailing operation has to be performed by striking about 10 times, which requires a great deal of labor and time and complicates the work. In addition, when the construction of the spray impermeable sheet is completed, the sprayed waterproofing agent is often permeated and coated, and the area around the nail shaft is watertight, but the nail hole sealability deteriorates over time and Water leakage from the surrounding area may occur, and the risk is particularly great when the construction site is an inclined surface. Further, in the case of fixing using a reaction-curing type adhesive, the adhesive is applied to a portion to be fitted to the shape of the ground surface in advance, in particular, a concave portion before laying the knitted fabric,
The knitted fabric is laid according to the curing time of the adhesive and fixed to the ground surface, but if the adhesive is applied at once, it is difficult to set the timing of the coating work and the knitting work of the fabric. Even if it is noticed that the fixed part is insufficient after laying the knitted fabric, there is a problem that the adhesive cannot be applied to the insufficient part at all.

The present invention is a construction method which has been made in order to solve the above-mentioned problems, and an object thereof is to provide a spraying method that surely fits the ground surface even when the ground surface to be laid has a large uneven surface. It is to provide a method of constructing a waterproof sheet.

[0007]

A method for constructing a sprayed water-impervious sheet according to the present invention is a hot-melt adhesive, in which low load stretchable knitted fabrics are laid on each other at their joints on a ground surface. After the back surface of the knitted fabric is fixed to the ground surface at a plurality of positions, a waterproofing agent is sprayed on the entire surface of the knitted fabric to form a water-impervious layer.

When the hot melt adhesive is applied to the back surface of the low load stretchable knitted fabric, the nozzle tip of the adhesive supply gun has a shape capable of penetrating the knitted fabric without damaging the knitted fabric.
Further, the ejection port for ejecting the adhesive may be performed by using an adhesive supply gun provided on the side surface near the tip of the nozzle.

The waterproofing agent is a rubber asphalt emulsion, which is sprayed by adding a slow coagulating agent before spraying.

[0010]

In the method for constructing a sprayed waterproof sheet according to the present invention, first, a low load stretchable knitted fabric is laid on the ground surface, but since the knitted fabric is stretched under a low load, it fits the uneven shape of the ground surface. Easy to wrinkle and no wrinkles.

Further, when a hot melt adhesive is applied to the back surface of the low load stretchable knitted fabric, an adhesive supply gun is used, but the tip of the nozzle can penetrate the knitted fabric without damaging the knitted fabric. Since it has, it is possible to insert the nozzle tip to the back side of the knitted fabric without damaging the yarn constituting the knitted fabric and the knitted fabric structure, and the nozzle has adhesive on the side face near the tip. Since the discharge port for discharging is provided, an appropriate amount of the melted adhesive is discharged toward the gap between the ground surface and the knitted fabric, and the knitted fabric is fixed to the ground surface as the adhesive cools.
Similarly, the knitted fabric is fixed to the ground surface at a plurality of places mainly on the ground surface concave portion over which the knitted fabric is laid, and the knitted fabric, along with its low load extensibility, follows the unevenness of the ground surface. Can be laid well.

After that, the waterproofing agent is sprayed on the entire surface of the knitted fabric, but the waterproofing agent is a rubber asphalt emulsion, and the rubber asphalt emulsion is coagulated by adding a slow coagulating agent to the rubber asphalt emulsion before use. Since it takes time until the sprayed rubber asphalt emulsion penetrates into the knitted fabric sufficiently and can penetrate into the ground surface, the waterproofing agent gradually solidifies to obtain a stable water-impervious sheet. At the same time, the laid water-impervious sheet can be well fixed to the ground surface, forming a water-impervious layer.

[0013]

EXAMPLES First, a low load stretchable knitted fabric used in the present invention,
The hot melt type adhesive, the adhesive supply gun for applying the hot melt type adhesive, and the waterproof agent will be described.

As the low load stretchable knitted fabric, a known one may be used, but from the viewpoint of low load stretchability, a structure in which the same yarn knitted by a weft knitting machine or a circular knitting machine is applied to a large number of needles Such a knitted fabric is preferable, and such a knitted fabric has loops formed by knitting needles continuous in the warp and weft directions, and when tensile stress is applied to the knitted fabric, the loops are easily deformed to expand and contract. The yarns that make up the knitted fabric are preferably made of synthetic fibers such as polyester, nylon, vinylon, and polyvinyl acetal, which have water resistance, corrosion resistance, and heat resistance, and the knitted fabric is stretchable to obtain low load extensibility. It is only necessary to use spandex yarn, undrawn yarn, multifilament false twisted yarn, etc. that have high properties. Multifilament false twisted yarn is the most suitable in consideration of bulkiness, waterproofing agent permeability, etc. The knitted fabric may be made into a double knit in order to obtain. In the present invention, the thickness of the knitted fabric is 2 to 4 mm in consideration of the thickness of the impermeable layer to be formed.
Degree.

As the hot-melt type adhesive, ethylene-vinyl acetate copolymer resin, polyamide resin, polyester resin alone, or those obtained by adding rosin or petroleum resin, styrene-butadiene rubber (SB)
R), styrene-butadiene-styrene rubber (abbreviation SB)
S), styrene / ethylene / butylene / styrene rubber (abbreviated as SEBS), styrene / isoprene / styrene rubber (abbreviated as SIS), and the like can be suitably used and have elasticity. However, those having a certain degree of tackiness are preferable.

After laying a low load stretchable knitted fabric on the ground surface,
As an adhesive supply gun for applying an adhesive to the back surface of the knitted fabric, the tip of the nozzle provided in the adhesive supply gun needs to penetrate the knitted fabric to reach the ground surface. The shape must be such that it can easily penetrate when passing through the knitted fabric and does not damage the yarn and the knitted fabric structure that form the knitted fabric, and that the nozzle tip reaches the ground surface and abuts it. An ejection port for the adhesive is provided on the side surface of the nozzle near the tip of the nozzle so that the adhesive can be ejected and reliably supplied into the space between the low load stretchable knitted fabric and the ground surface.

FIG. 1 shows a concrete structure of such an adhesive supply gun.
And the configuration will be described. In the figure, 11 denotes an adhesive supply gun, and the adhesive supply gun 11 is connected to an adhesive supply source 12 via a heater hose 13.

The adhesive supply gun 11 has, for example, a length on the tip side.
30 to 50 mm, inner diameter 1.0 to 1.8 mm, outer diameter 1.2 to 2.0
A stainless steel nozzle 14 having a size of about mm is provided, a hand lever 15 is provided on the rear end side, and a heating device 16 having a heater therein is provided at an intermediate portion thereof. The diameter is 0.5 to 1.0 mm on the side of the nozzle 14 which is about 2 to 5 mm from the tip of the nozzle 14.
Two or more discharge ports 17 of a certain degree are provided.

The adhesive supply source 12 is provided with a container 19 made of, for example, aluminum for storing the hot melt adhesive 18, and a heater plate 20 for heating the adhesive 18 in the container 19 to a predetermined temperature. A cylinder 22 that presses the heated adhesive 18 toward the supply port 21 is provided. Then, the adhesive 18 heated by being pressed by the operation of the cylinder 22 is supplied from the supply port 21 to the adhesive supply gun 11 via the heater hose 13.

Examples of the waterproofing agent include known asphalt-based emulsions, urethane-based liquid polymer emulsions, asphalt-urethane-based emulsions and the like. From the viewpoints of durability, weather resistance, water resistance, etc., asphalt-based emulsions, particularly rubber asphalt. It is preferable to use an emulsion. In addition, the rubber asphalt emulsion and the calcium chloride aqueous solution as a coagulant are simultaneously sprayed from separate nozzles, and sprayed while they are contact-mixed immediately before reaching the adhered point, and then sprayed on the base material at the adhered point. It forms a water-impervious layer of rubber asphalt, but since the spraying liquid that forms the water-impervious layer is instantly binding, it is suitable when the thickness of the low-load extensible knitted fabric is thin,
In the case of a thick knitted fabric, it is desirable that the spray liquid sufficiently penetrates into the knitted fabric and then solidifies. Therefore, instead of the calcium chloride aqueous solution, use an ammonium salt aqueous solution containing alcohol as a slow coagulating agent and oxidize it. A waterproofing agent mixed with a rubber asphalt emulsion containing zinc or magnesium oxide.

[0021] In the present invention, the term "ground surface" refers to the ground surface of a place where water is to be blocked, such as a waste disposal site, a general civil engineering adjustment pond, a reservoir, or a water channel. A low-load stretchable knitted fabric laid on the ground surface In order for the adhesive applied between the ground surface and the ground surface to securely fix them, it is advisable to finish the water-impregnated ground surface in advance with a concrete surface, mortar surface or spray mortar surface. .

Next, specific examples of the present invention will be described.

1 and 2 show an example of the embodiment of the present invention.

First, as shown in FIG. 1, a ground surface (slope) 2 consisting of a mortar base layer having a thickness of 70 mm is formed on an inclined landfill 1 of a waste disposal site by spraying mortar, and then, Low-load stretchable knitted fabric 3 (polyester knitted fabric, manufactured by Toyobo Co., Ltd., trade name Cosmoliner YK24, which is 3.2 mm thick, 3.4 m wide, and 23 m long wound on the ground surface 2.
24) is placed and the winding end of the roll-shaped low-load stretchable knitted fabric 3 is aligned with the slope shoulder of the inclined ground surface 2, and the load is reduced from the upper side to the lower side of the ground surface 2. While unwinding the stretchable knitted fabric 3, it was laid along the uneven surface of the ground surface 2 so that the low load stretchable knitted fabric 3 fits well.

Next, as shown in FIG. 2, the low load stretchable knitted fabric 3 previously laid on the ground surface 2 (left side in the example shown in FIG. 2).
Next to the low load stretchable knitted fabric 3 (on the right side in the example shown in FIG. 2), the next low load stretchable knitted fabric 3 is laid on the edge of the low load stretchable knitted fabric 3 previously laid.
Sequential laying was performed while taking a 200 mm overlapping portion, and this overlapping portion was used as the joining portion 4.

After laying a plurality of low-load extensible knitted fabrics 3 on the ground surface 2, the adhesive-loading gun 11 (manufactured by Polymer Systems Co., Ltd.) is used to form the low-load extensible knitted fabrics by the unevenness of the ground surface 2. Aiming at the point where 3 is raised from the mortar base surface as much as possible, as shown in FIG.
Between the low load stretchable knitted fabric 3 and the hot melt adhesive 1
8 (Mitsui Toatsu Chemical Co., Ltd., trade name MT Melt T-
808) was discharged to fix the low load stretchable knitted fabric 3 on the ground surface 2.

The nozzle 14 of the adhesive supply gun 11 is made of stainless steel having an outer diameter of 2 mm, an inner diameter of 1 mm, and a length of 30 mm.
Two discharge ports 17 for discharging 8 were provided in exactly opposite directions. When the hot melt adhesive 18 is discharged between the ground surface 2 and the low load stretchable knitted fabric 3,
As shown in FIG. 1, the low load stretchable knitted fabric 3 is picked up by the hand H and pulled up, and the low load stretchable knitted fabric 3 is pulled up.
The tip of the nozzle 14 of the adhesive supply gun 11 penetrates through the stitches of the knitted fabric, and the handle lever 15 of the adhesive supply gun 11 is provided between the back surface side of the low load stretchable knitted fabric 3 portion and the ground surface 2. To discharge. At that time, since the knitted fabric 3 has low load extensibility, the knitted fabric 3 can be easily picked up by the hand H and pulled up, and when the knitted fabric 3 is pulled, the stitches can be easily stretched. The tip of the nozzle 14 of the gun 11 can be penetrated from the front side to the back side of the knitted fabric 3 without damaging the stitch.

The amount of adhesive discharged per stroke of the handle lever 15 of the adhesive supply gun 11 is about 0.5c.
Since it was c, 1 of the low load stretchable knitted fabric 3 to the ground surface 2
To fix each part, the handle lever 15 was operated by three strokes and about 1.5 cc of the adhesive 18 was used.

Although the amount of the adhesive 18 used for fixing the low load stretchable knitted fabric 3 to the ground surface 2 is sufficient, the unevenness of the ground surface 2 and the low load stretchable knitted fabric 3 The amount of adhesive used can be appropriately increased or decreased by changing the number of operations of the handle lever 15 of the adhesive supply gun 11 depending on the material, thickness and the like.

After the adhesive 18 is filled between the ground surface 2 and the low load stretchable knitted fabric 3, the portion is pressed from above the low load stretchable knitted fabric 3 using a roller or the like to reduce the load. The stretchable knitted fabric 3 is brought into close contact with the ground surface 2 and left to stand until the hot melt adhesive 18 is cooled and cured. The standing time depends on the material, thickness, etc. of the low load extensible knitted fabric 3, the type of hot melt adhesive, the viscosity, the filling amount, etc., the condition of the ground surface 2 on which the low load extensible knitted fabric 3 is laid, and the weather conditions. Although different, in the case of the above embodiment, about 3 to 5 seconds is sufficient.

Further, in the above-mentioned embodiment, the fixing portion of the low load stretchable knitted fabric 3 on the ground surface 2 is 1 square meter (1 m ² ).
However, the number of fixing points may be appropriately set depending on the condition of the ground surface 2, the material of the low load stretchable knitted fabric 3 and the thickness.

Further, as shown in FIG. 2, the joining method of the joining portion 4 of the low-load extensible knitted fabric 3 laid on the low-load extensible knitted fabric 3 previously laid on the ground surface 2 is as follows. The hot-melt adhesive 18 is applied along the edge 5 of the low-load stretchable knitted fabric 3 laid previously, and then the hot-melt adhesive 18 is applied in zigzag at the planned location of the joint 24. ,
Further, after applying the hot-melt type adhesive 18 along the position corresponding to the edge 5 of the low load stretchable knitted fabric 3 laid afterwards, the end portions of both low load stretchable knitted fabrics 3 are overlapped with each other to form a roller. It suffices to form the joint portion 4 by pressing and joining with each other.

After the low load stretchable knitted fabric 3 is fixed on the ground surface 2, the rubber asphalt emulsion and the slow coagulant are mixed in a ratio of 10: 1 over the entire surface of the low load stretchable knitted fabric 3. Spray waterproofing agent 6 (manufactured by Nisshin Kogyo Co., Ltd., trade name PLENO-P
1 square meter (1m of coat [solid content 65.5% by weight])
² ) 6 kg per spray (arrow 6 in FIG. 1) was sprayed, and the low-load stretchable knitted fabric 3 was sufficiently permeated and coated, and the waterproofing agent 6 was solidified to form the water-impervious layer 7.

After the above-mentioned construction, a protective layer agent (manufactured by Nisshin Kogyo Co., Ltd., trade name Plentop) consisting of acrylic emulsion and water-cured powder is sprayed on the water-blocking layer 7 to form a protective layer (as shown). May be formed.

[0035]

According to the method of the present invention, low load extensible knitted fabrics are laid on each other at their joints on the ground surface, and the back surface of the knitted fabric is laid on the ground surface with a hot melt adhesive. After fixing it at multiple places on the knitted fabric, a waterproofing agent was sprayed on the entire surface of the knitted fabric to form a water-impervious layer, so that a large amount of construction work such as when using conventional nails or concrete nails was required. A nail of a waterproof sheet that can easily fix a low-load stretchable knitted fabric on the ground surface without requiring construction time and can be laid on the ground surface over time after construction, as when using a nail. There is no risk of water leakage as the hole sealability deteriorates.

As in the case of using a conventional reaction-curing type adhesive, the adhesive is applied before the waterproof sheet is laid on the ground surface, and the timing of the curing time of the adhesive is measured. There is no complexity of laying a waterproof sheet, and it is possible to easily fill the adhesive after laying a low load stretchable knitted fabric on the ground surface, and determine the fit situation of the low load stretchable knitted fabric to the ground surface. Since the adhesive fixing point can be selected after that, the low load stretchable knitted fabric can be laid very well along the unevenness of the ground surface.

Further, when a hot melt type adhesive is applied to the back surface of the low load extensible knitted fabric, an adhesive having a nozzle which penetrates the stitches of the knitted fabric without damaging the low load extensible knitted fabric at the tip. When a hot-melt adhesive is applied using a supply gun, the material that forms the water-blocking layer laid on the ground surface is composed of a low-load stretchable knitted fabric, so the area where the adhesive is filled is low. Since the load stretchable knitted fabric can be easily pulled up, it is possible to extremely easily fill the adhesive between the ground surface and the low load stretchable knitted fabric, and to extend the low load stretched on the ground surface. The flexible knitted fabric can be fixed easily and surely.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a main part of a construction of one embodiment of the method of the present invention,

FIG. 2 is an explanatory view of a laid state of a low load stretchable knitted fabric.

[Explanation of symbols]

2 Ground surface, 3 Low load stretchable knitted fabric, 4
Joining part, 6 waterproofing agent, 7 impermeable layer, 1
1 adhesive supply gun, 14 nozzles, 17
Discharge port, 18 adhesive.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasunori Ueda Nisshin Special Construction Co., Ltd. 2-21-28 Senjuhigashi, Adachi-ku, Tokyo (72) Inventor Yoji Tanaka 2-chome, Odai, Miyamae-ku, Kawasaki-shi, Kanagawa 6-2 In Polymer Systems Co., Ltd. (72) Inventor Katsuaki Sekihara 2-23-4 Senjuhigashi, Adachi-ku, Tokyo Nisshin Kogyo Co., Ltd. (72) Injun Akitagi Toji Senju, Adachi-ku, Tokyo 23-4, Nissin Kogyo Co., Ltd. (56) Reference JP-A-3-147919 (JP, A)

Claims (4)

(57) [Claims] 1. A low-load extensible knitted fabric is laid on the ground surface so as to overlap each other at its joints, and the back surface of the knitted fabric is fixed to the ground surface at a plurality of points by a hot melt adhesive. A method for constructing a sprayed waterproof sheet, comprising spraying a waterproofing agent on the entire surface of the knitted fabric to form a waterproof layer. 2. An adhesive provided with a nozzle that penetrates the stitches of the knitted fabric without damaging the low load extensible knitted fabric when applying a hot-melt type adhesive to the back surface of the low load extensible knitted fabric. The method for constructing a sprayed waterproof sheet according to claim 1, wherein the hot-melt adhesive is applied using a supply gun. 3. The spray water impervious sheet construction according to claim 2, wherein the nozzle of the adhesive supply gun is provided with a discharge port for discharging the adhesive on a side surface near the tip thereof. Method. 4. The waterproofing agent is a rubber asphalt emulsion,
4. A slow coagulating agent is added before spraying a waterproofing agent to spray the waterproofing agent.
The method for constructing a sprayed water-blocking sheet according to paragraph.